I need to install an attic access door in my new 30'*32'*12' woodshop.what is the procedure for modifying the ceiling joust to accomodate a 24" wide door? Do I have to add any temporary support to cut the joust in the way? I plan on adding double 2x10 at both ends of the opening. For info, it is framed with a 7"x18" paralam beam in the center and 2x10's on 19" centers.